ethtool: Centralise validation of ETHTOOL_{G, S}RXFHINDIR parameters

Add a new ethtool operation (get_rxfh_indir_size) to get the
indirectional table size.  Use this to validate the user buffer size
before calling get_rxfh_indir or set_rxfh_indir.  Use get_rxnfc to get
the number of RX rings, and validate the contents of the new
indirection table before calling set_rxfh_indir.  Remove this
validation from drivers.

Signed-off-by: Ben Hutchings <bhutchings@solarflare.com>
Acked-by: Dimitris Michailidis <dm@chelsio.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

3 files changed, 40 insertions, 61 deletions

diff --git a/drivers/net/ethernet/broadcom/bnx2x/bnx2x_ethtool.c b/drivers/net/ethernet/broadcom/bnx2x/bnx2x_ethtool.c
index 90d44af8560..a688b9d975a 100644
--- a/drivers/net/ethernet/broadcom/bnx2x/bnx2x_ethtool.c
+++ b/drivers/net/ethernet/broadcom/bnx2x/bnx2x_ethtool.c
@@ -2302,18 +2302,20 @@ static int bnx2x_get_rxnfc(struct net_device *dev, struct ethtool_rxnfc *info,
 	}
 }
 
-static int bnx2x_get_rxfh_indir(struct net_device *dev,
-				struct ethtool_rxfh_indir *indir)
+static u32 bnx2x_get_rxfh_indir_size(struct net_device *dev)
+{
+	struct bnx2x *bp = netdev_priv(dev);
+
+	return (bp->multi_mode == ETH_RSS_MODE_DISABLED ?
+		0 : T_ETH_INDIRECTION_TABLE_SIZE);
+}
+
+static int bnx2x_get_rxfh_indir(struct net_device *dev, u32 *indir)
 {
 	struct bnx2x *bp = netdev_priv(dev);
-	size_t copy_size =
-		min_t(size_t, indir->size, T_ETH_INDIRECTION_TABLE_SIZE);
 	u8 ind_table[T_ETH_INDIRECTION_TABLE_SIZE] = {0};
 	size_t i;
 
-	if (bp->multi_mode == ETH_RSS_MODE_DISABLED)
-		return -EOPNOTSUPP;
-
 	/* Get the current configuration of the RSS indirection table */
 	bnx2x_get_rss_ind_table(&bp->rss_conf_obj, ind_table);
 
@@ -2326,33 +2328,19 @@ static int bnx2x_get_rxfh_indir(struct net_device *dev,
 	 * align the returned table to the Client ID of the leading RSS
 	 * queue.
 	 */
-	for (i = 0; i < copy_size; i++)
-		indir->ring_index[i] = ind_table[i] - bp->fp->cl_id;
-
-	indir->size = T_ETH_INDIRECTION_TABLE_SIZE;
+	for (i = 0; i < T_ETH_INDIRECTION_TABLE_SIZE; i++)
+		indir[i] = ind_table[i] - bp->fp->cl_id;
 
 	return 0;
 }
 
-static int bnx2x_set_rxfh_indir(struct net_device *dev,
-				const struct ethtool_rxfh_indir *indir)
+static int bnx2x_set_rxfh_indir(struct net_device *dev, const u32 *indir)
 {
 	struct bnx2x *bp = netdev_priv(dev);
 	size_t i;
 	u8 ind_table[T_ETH_INDIRECTION_TABLE_SIZE] = {0};
-	u32 num_eth_queues = BNX2X_NUM_ETH_QUEUES(bp);
-
-	if (bp->multi_mode == ETH_RSS_MODE_DISABLED)
-		return -EOPNOTSUPP;
-
-	/* validate the size */
-	if (indir->size != T_ETH_INDIRECTION_TABLE_SIZE)
-		return -EINVAL;
 
 	for (i = 0; i < T_ETH_INDIRECTION_TABLE_SIZE; i++) {
-		/* validate the indices */
-		if (indir->ring_index[i] >= num_eth_queues)
-			return -EINVAL;
 		/*
 		 * The same as in bnx2x_get_rxfh_indir: we can't use a memcpy()
 		 * as an internal storage of an indirection table is a u8 array
@@ -2362,7 +2350,7 @@ static int bnx2x_set_rxfh_indir(struct net_device *dev,
 		 * align the received table to the Client ID of the leading RSS
 		 * queue
 		 */
-		ind_table[i] = indir->ring_index[i] + bp->fp->cl_id;
+		ind_table[i] = indir[i] + bp->fp->cl_id;
 	}
 
 	return bnx2x_config_rss_pf(bp, ind_table, false);
@@ -2395,6 +2383,7 @@ static const struct ethtool_ops bnx2x_ethtool_ops = {
 	.set_phys_id		= bnx2x_set_phys_id,
 	.get_ethtool_stats	= bnx2x_get_ethtool_stats,
 	.get_rxnfc		= bnx2x_get_rxnfc,
+	.get_rxfh_indir_size	= bnx2x_get_rxfh_indir_size,
 	.get_rxfh_indir		= bnx2x_get_rxfh_indir,
 	.set_rxfh_indir		= bnx2x_set_rxfh_indir,
 };
diff --git a/drivers/net/ethernet/chelsio/cxgb4/cxgb4_main.c b/drivers/net/ethernet/chelsio/cxgb4/cxgb4_main.c
index a34e7ce7e21..8ffd55bdef3 100644
--- a/drivers/net/ethernet/chelsio/cxgb4/cxgb4_main.c
+++ b/drivers/net/ethernet/chelsio/cxgb4/cxgb4_main.c
@@ -1871,30 +1871,30 @@ static int cxgb_set_features(struct net_device *dev, netdev_features_t features)
 	return err;
 }
 
-static int get_rss_table(struct net_device *dev, struct ethtool_rxfh_indir *p)
+static u32 get_rss_table_size(struct net_device *dev)
 {
 	const struct port_info *pi = netdev_priv(dev);
-	unsigned int n = min_t(unsigned int, p->size, pi->rss_size);
 
-	p->size = pi->rss_size;
+	return pi->rss_size;
+}
+
+static int get_rss_table(struct net_device *dev, u32 *p)
+{
+	const struct port_info *pi = netdev_priv(dev);
+	unsigned int n = pi->rss_size;
+
 	while (n--)
-		p->ring_index[n] = pi->rss[n];
+		p[n] = pi->rss[n];
 	return 0;
 }
 
-static int set_rss_table(struct net_device *dev,
-			 const struct ethtool_rxfh_indir *p)
+static int set_rss_table(struct net_device *dev, const u32 *p)
 {
 	unsigned int i;
 	struct port_info *pi = netdev_priv(dev);
 
-	if (p->size != pi->rss_size)
-		return -EINVAL;
-	for (i = 0; i < p->size; i++)
-		if (p->ring_index[i] >= pi->nqsets)
-			return -EINVAL;
-	for (i = 0; i < p->size; i++)
-		pi->rss[i] = p->ring_index[i];
+	for (i = 0; i < pi->rss_size; i++)
+		pi->rss[i] = p[i];
 	if (pi->adapter->flags & FULL_INIT_DONE)
 		return write_rss(pi, pi->rss);
 	return 0;
@@ -1989,6 +1989,7 @@ static struct ethtool_ops cxgb_ethtool_ops = {
 	.get_wol           = get_wol,
 	.set_wol           = set_wol,
 	.get_rxnfc         = get_rxnfc,
+	.get_rxfh_indir_size = get_rss_table_size,
 	.get_rxfh_indir    = get_rss_table,
 	.set_rxfh_indir    = set_rss_table,
 	.flash_device      = set_flash,
diff --git a/drivers/net/ethernet/sfc/ethtool.c b/drivers/net/ethernet/sfc/ethtool.c
index f3cd96dfa39..1be51b2bfa4 100644
--- a/drivers/net/ethernet/sfc/ethtool.c
+++ b/drivers/net/ethernet/sfc/ethtool.c
@@ -956,40 +956,28 @@ static int efx_ethtool_set_rx_ntuple(struct net_device *net_dev,
 	return rc < 0 ? rc : 0;
 }
 
-static int efx_ethtool_get_rxfh_indir(struct net_device *net_dev,
-				      struct ethtool_rxfh_indir *indir)
+static u32 efx_ethtool_get_rxfh_indir_size(struct net_device *net_dev)
 {
 	struct efx_nic *efx = netdev_priv(net_dev);
-	size_t copy_size =
-		min_t(size_t, indir->size, ARRAY_SIZE(efx->rx_indir_table));
 
-	if (efx_nic_rev(efx) < EFX_REV_FALCON_B0)
-		return -EOPNOTSUPP;
+	return (efx_nic_rev(efx) < EFX_REV_FALCON_B0 ?
+		0 : ARRAY_SIZE(efx->rx_indir_table));
+}
+
+static int efx_ethtool_get_rxfh_indir(struct net_device *net_dev, u32 *indir)
+{
+	struct efx_nic *efx = netdev_priv(net_dev);
 
-	indir->size = ARRAY_SIZE(efx->rx_indir_table);
-	memcpy(indir->ring_index, efx->rx_indir_table,
-	       copy_size * sizeof(indir->ring_index[0]));
+	memcpy(indir, efx->rx_indir_table, sizeof(efx->rx_indir_table));
 	return 0;
 }
 
 static int efx_ethtool_set_rxfh_indir(struct net_device *net_dev,
-				      const struct ethtool_rxfh_indir *indir)
+				      const u32 *indir)
 {
 	struct efx_nic *efx = netdev_priv(net_dev);
-	size_t i;
-
-	if (efx_nic_rev(efx) < EFX_REV_FALCON_B0)
-		return -EOPNOTSUPP;
-
-	/* Validate size and indices */
-	if (indir->size != ARRAY_SIZE(efx->rx_indir_table))
-		return -EINVAL;
-	for (i = 0; i < ARRAY_SIZE(efx->rx_indir_table); i++)
-		if (indir->ring_index[i] >= efx->n_rx_channels)
-			return -EINVAL;
 
-	memcpy(efx->rx_indir_table, indir->ring_index,
-	       sizeof(efx->rx_indir_table));
+	memcpy(efx->rx_indir_table, indir, sizeof(efx->rx_indir_table));
 	efx_nic_push_rx_indir_table(efx);
 	return 0;
 }
@@ -1020,6 +1008,7 @@ const struct ethtool_ops efx_ethtool_ops = {
 	.reset			= efx_ethtool_reset,
 	.get_rxnfc		= efx_ethtool_get_rxnfc,
 	.set_rx_ntuple		= efx_ethtool_set_rx_ntuple,
+	.get_rxfh_indir_size	= efx_ethtool_get_rxfh_indir_size,
 	.get_rxfh_indir		= efx_ethtool_get_rxfh_indir,
 	.set_rxfh_indir		= efx_ethtool_set_rxfh_indir,
 };